Carbureter.



PATENTED SEPT. 10, 1907.

A. c. STEWART.

UARBURETER.

APPLICATION FILED FEB.6,1905.

.2 SHEETS-SHEET 1.

@igj

' iimi A. C. STEWART.

GARBURETER. APPLICATION FILED P213. 6. 1905.

2 SHEETS-SHEET 2.

Wna

n4: NORRIS pn'sns cm. WAsNIMcrON. D. c.

ALFRED C. STEWART, OF LOS ANGELES; CALIFORNIA.

CARBURETER.

Specification of Letters Patent.

Patented Sept. 10, 1907.

Application filed February 6, 1905. srial N0. 244,337.

To all whom it may concern:

Be it known that I, ALFRED O. STEWART, a citizen of the United States,residing at Los Angeles, in the county of Los Angeles and State ofCalifornia, have invented a new and useful Improvement in Carbureters,of which the following is a specification.

The main object of this invention is to provide a carbureter forinternal combustion engines that will produce a mixture of substantiallyuniform or constant quality of richness under different conditions ofworking; for example, at different speeds.

A further object of the invention is to provide for uniform or thoroughdistribution of the combustible and the air throughout the mixture.

Another object of the invention is to do away with the excessivechilling of the carburetor connections that sometimes occurs, and alsodispense with the use of special warming devices.

Carbureters now in general use supply the oil or fluid fuel to an outletfrom which it is drawn by the injector or entraining effect of a currentof air passing said outlet on its way to the admission port of theengine. It is necessary to have the oil supplied at a levela littlebelow the outlet so that it will not flow except when drawn out by thesuction of the air, but in order to supply sufficient oil when theengine is just starting, this difference of level must be very slight.The amount of oil drawn from the outlet by the air increases with thevelocity of the air and therefore with the speed of the engine, and ifthe oil supply is at the right levelfor low speed the increase of flowat high speeds will furnish an over-supply of oil. An attempt has beenmade to correct this by a by-pass inlet valve opening against thepressure of a spring to allow air to flow to and dilute the mixturewithout passing the oil outlet, but the correction thereby obtained isimperfect. Such carburetors also introduce the oil in an uneven orundistributed mannor, as the oil does not have time to become diffusedor distributed throughout the mixture, but is thrown or drawn in dropsof greater or less size either directly into the explosion chamber oragainst any bend or wall that may lie in its course. In the latter case,part will evaporate into the air passing over it, but this will producean undesirable chilling of the parts. If heat be applied to the mixtureto expedite the diffusion and overcome the chilling effect, theefficiency of the engine is lowered.

In the present invention, the entraining of the oil by the motion of theair thereover is dispensed with as being unreliable in its operation,and a system is substituted of supplying oil under definite, directsuctional action, the effect of which can be graduated to producesubstantially uniform conditions of mixture under varying conditions ofengine speed. i

The invention also provides means for applying to the oil, after it haspassed from the outlet, a current of air of definite velocityconcentrated on the oil in such manner as to produce thoroughatomization or spraying thereof and diffusion of the oil throughout themixture.

The accompanying drawings illustrate the invention, and referringtheretoz-Figure 1 is a side elevation partly in section. Fig. 2 is asection on line 1 in Fig. 1. Fig. 3 is a section on line an -x inj IFig. 1. Fig. 4 is a section on line af-x in Fig. 1; if

Fig. 5 is a section on line 90 -1 in Fig. 2, Fig. 6 is an elevation of aregulating sleeve for the air inlet. Fig. 7 is a sectional elevation ofpart of the carbureter having a different form of the regulating sleeve.Figs. 8 and 9 are developments showing different forms of the air inletports.

1 designates the tubular body of the carbureterwhi'eh has the floatchamber 2 formed on or connected to the side thereof. A chamber ormember 3 may be con I neeted to the member 1 and may serve as a combined7 throttle valve and mixing chamber. The float chamber Z-has an oilinlet 4 at the bottom connected to the oil supply pipe 5, the passage ofoil from this inlet to the float chamber being controlled by a valve 6operated by the float 7 in the usual manner, said float having a stem 8working in a guide 9 at the top of the float chamber.

A passage or duct 10 leads from the float chamber 2 through the wall ofthe tubular member 1 into an annular chamber or recess 11 formed in saidwall or in a flange 12 on the inner side thereof, communication throughduct 10 being controlled by a valve 13. The annular chamber or recess 11communicates with the interior of the tubular member 1 through a seriesof orifices 14 extending preferably upwardly and inwardly from saidchamber. Said orifices may be formed in a ring 15 that is secured withinthe tubular member 1 and on top of the flange 12, being held inposition, for example, by the screw-threaded lower end 3 of member 3screwing 9h into the member 1 and bearing down on the ring 15.

The tubular member 1 is provided, below the oil communications, abovedescribed, with a series of air inlets or openings 16 in its wall, thecommunication through these openings from the outer air to the interiorof the tubular member 1 being controlled by a regulating sleeve 17 and asliding valve-ring 18. Regulating-sleeve 17 slides within tubular member1 and has a series of ports or openings 17 a corresponding to the portsor openings 16 in the tubular member 1, and the valve ring 18 slideswithin the sleeve 17 and constricts or closes or opens communicationthrough the aforesaid ports, as hereinafter described. Regulating-ring17 is movable or adjustable both circumferentially or rotatably andvertically or longitudinally of the tubular member 1, and means areprovided for fastening the said regulating sleeve when it has beenbrought or moved to proper circumferential and longitudinal position.For this purpose a screw-stud 19 (see Figs. 1 and 2), may extendoutwardly from an enlargement 17 of the regulatingsleeve, the tubularmember 1 being provided in its wall with a circumferential slot 20 forthe passage of said stud, said slot being of sufficient extent in bothcircumferential and vertical directions to permit of a limited movementof said stud in both directions, sufficient for its adjustment ashereinafter described, and a clamping nut 21 being provided on said studto bind against the outside of a se mental plate 22 which slides on andaround the outer wall of the member 1, the nut 21 in binding the sleeve17 and plate 2201i member 1 serving to clamp the sleeve 17 in fixedposition within the tubular member. Substantially the same adjustmentmay be obtained in other ways as by forming the ring (see 17 in Fig. 7)with a screw portion 39 screwing in the bottom of tubular member 1, andproviding a set screw 40, if necessary to set the ring in adjustedposition. The circumferential adjustment is then obtained by a slightangular movement of the ring, and vertical adjustment by one or morecomplete rotations thereof.

The sliding valve-ring 18 is carried by a spid r or valve member 23attached to a stem or rod 24 which extends vertically and axially of thetubular member 1 and is slidably supported by arms 25 extendingiiiwardly from the flange 12. Valve-carrier 23 is provided with a piston26 at its lower end of a diamete approaching that of the tubular member]so that said piston will work up and down within said tubular memberpreferably without touching the same, but so, close thereto as to retardor restrict the passage of air from one side to the other of the pistonand thereby acting in the manner of a dash-pot to retard the movement ofthe valve. 2 The lower end of the tubular member 1 in the form shown inFig. .1 may be provided with a closure formed as a head 30 screwing intosaid member 1. This valve device is operated by a device responsive tothe suetiona-l pressure of the air as it is drawn into the enginecylinder. For this purpose a deflector-plate 27 is provided at the upperend of the valve stem 24, said deflector-plate. being of a diameterapproximating that of the opening formed by the upper end of the ring15. Ring 15 has an annular recess 15", and the portion of said ringabove said recess is preferably upwardly eon vergent or tapering; forexample, in the concavely curved form shown. so as to produce aninternal annular kniveedge or lip 15" surrounding the outlet opening attop of chamber 1, and the deflector-plate 27 when in its lowermostposition will approximately fit within and nearly touch this annularedge. The deflectorplate is also preferably provided with a bevel rim 29forming an annular knife-edge.

The deflector-plate 27 serves in the first place as a means foroperation of the valve or constricting means 18 for the air inletopenings by the suctional effect at the outlet opening, and in thesecond place it serves as a constricting or closure device for theoutlet opening so as to concentrate the flow of air thereat, ashereinafter explained.

The orifices 14 open into the recess 15 of ring 15 and said ring has anannular inwardly inclined surface below said orifices, extending to theflange 12 so that the oil supply means or connection opens into thechamber of member 1 out of the path of movement of the closure ordeflector means and communicates continually with said chamberirrespective of such movement.

While the above described carburetor can be used in connection with anysuitable fittings to lead the mixture therefrom to the engine, I preferto provide in connection therewith the combined mixing chamber andthrottle-valve 3 shown in the drawing which provides in thethrottle-valve chamber itself sufficient space to allow the oil, whichis sprayed into the air as it passes the members 15 and 27, to diffuseand quickly distribute itself as vapor throughout the air before themixture reaches the outlet of the throttle-valve.

The chamber 3 is preferably cylindrical with its axis horizontal and itsoutlet either at the top or at theupper portion of one side so that afull opportunity for the vaporization and mixture of the oil will bepermitted before the same reaches the outlet. The throttlevalves closuremember 31 is formed as a wing on a sleeve 32 passing through thethrottle-shaft 33 which extends axially of the cylindrical member 3,said wing having a segmental arm or plate 34 extending parallel and insliding proximity to the cylindrical wall of said chamber.

An opening 35 is provided in the end wall of the chamber 3 to be closedor opened by the wing 31, and anotheropening 36 is provided in the topof said chamber 3 to be closed or opened by the segmental arm 34.

Connection with the engine may be made by a coupling or connectingdevice entering either one of the openings 35, 36, according to whichgives the most direct passage or is most convenient under thecircumstances, the other opening being closed .by suitable plug, cap orother closure means, indicated at 37.

The operation of the carburetor is as foll0ws:When the engine is at restthe valve device 23, 24, 27, will be in lowermost position with thepiston 26 resting on the bottom plate 30, and the deflector 27 is on alevel with the internal annular edge of the ring 15 and so close to thesame that only an inconsiderable quantity of air can pass withoutlifting the said deflector. As the engine is turned over and begins todraw in air, it will create a condition of suction orpartial vacuumwithin the chamber 3 and the pressure of the air on the lower face ofthe deflector 27 will raise the deflector and valve device 27, 24, 23,this movement being gradual on account of the retarding action of thepiston 26,

The regulating sleeve 17 is assumed to have been set by longitudinal andcircumferential adjustment in such manner that as the deflector 27 risesthe ports at 17 will be opened by the sliding valve ring 18 sufficientlyto maintain a definite condition of suction or vacuum gradually anddefinitely increasing in proportion to the amount of indraft and thespeed of the engine, so as to maintain the proper conditions for uniformmixture at all speeds. The oil-supply regulating float-device 2, 7, isso constructed as to maintain the level of the oil approximately at thelevel of or slightly below the discharge outlets or orifices 14 whenthere is no suction in the inner tubular member, so that the conditionof suction above-mentioned will result in a definite and graduated flowof the oil into the inner tubular member or chamber 2. On the otherhand, this flow will not in any way be influenced by any entraining orinjector effect of the air. To insure this, the

flange 12 is made to extend out to the same distance as the internalannular lip of ring 15, and the discharge orifices 14 open into'theannular recess 15 and are thus out of the path of the direct flow of airupwardly toward the discharge outlet between the members 15 and 27. Whenthe oil has been drawn from the orifices 14 by the suctional effect ofthe partial vacuum within the chamber 1 it will spread over the surfaceof the recess 15 and will sooner or later be caught by the ascendingcurrent of air passing up within the flange 12 and will be carried overthe internal annular lip 15 and between said lip and the deflector 14.In the operation of the valve device 23, 24, 27, as abovedescribed, thepiston 26 serves to dampen or retard the movement thereof so as to avoidany interference with the gradual and uniform regulating action by theinertia or momentum of the said valve devices.

The regulating sleeve 17 is set for proper operation in the followingmanner:Tl1e binding screw 21 is loosened and said sleeve is moved upfrom its lowermost position until the lower edge of the ports 17"approximate so closely to the lower edge of valve-ring 18, when thelatter is in lowermost position, that just the proper condition ofsuction will be obtained in starting up to draw the requisite amount ofoil from the orifices 14 to properly start the engine. The engine isthen started up and when it is running at full speed it will be foundthat the amount of oil supplied will, with the above adjustment, givemore than the required or proper quantity of oil supply. The regulatingsleeve 17 is then circumferentially adjusted or moved, while maintainingthe definite horizontal position to whichit has already been brought bythe above-described adjustment, until the walls 17 between the ports 17overlap the outer ports 16 sufficiently to cut down or reduce thedimensions thereof sufficiently to restore the proper condition ofpartial vacuum or suction within the tubular member 1.

The proper operation of the regulating devices to secure uniform mixtureat different speeds can be effected by longitudinal and circumferentialadjustment of the regulating sleeve 17 or 17 as determined by practice.The ports in said sleeve may be rectangular or may be slanting or curvedat one or both sides as indicated in Figs. 8 and 9, according to thespecial condition and the variation desired.

What I claim is:

l. A carburetor comprising a tubular chamber having an outlet,and'provided with air inlet ports. means for applylug suction to saidoutlet, at regulating device adjustable within said chamber to vary theextension of said inlet ports longitudinally of the chamber, a valvemember movable longitudinally within said regulating device. meansconnected to operate said valve, illld responsive to the suction at theoutlet, and an oil supply connection opening into said chamber.

2. A carbureter comprising a tubular chamber having an outlet, andprovided with air inlet ports, means for applying suction to saidoutlet, a regulating device adjustable within said chamber to vary theextension of said ports longitudinally and circumferentially of thechamber. a valve member movable within said regulating device, meansconnected to operate said valve member, and responsive to the suction atthe outlet, and an oil supply connection Opening into said chamber,

3. A carburetercomprising a tubular chamber having an outlet, andprovided with air inlet ports, means for applying suction to saidoutlet, a regulating device adjustable within said chamber to vary theextension of said ports circumferentially of the chamber, a valve membermovable longitudinally within said regulating device, means connected tooperate said valve member and responsive to the suction at the outlet,and an oil supply connection opening into said chamber.

4. A carbureter comprising a chamber having air inlet and mixture outletopenings and a recessed portion be: tween said openings, oil supplymeans opening into said recessed portion, a valve for constricting andclosing the air inlet opening and a deflector connected to said valvefor constricting the outlet opening, said oil supply connection openinginto said chamber out of the path of movement of said deflector, andbeing continually in communication with the chamber, irrespective of themovement of the deflector.

5. A carbureter comprising a chamber having air inlet and mixture outletopenings, and having an inwardly extending lip around the outlet openingan oil supply connection to said chamber, means for applying suction tothe outlet opening, a valve device controlling the inlet opening and adeflector connected to the valve device and of approximately the samediameter as the outlet opening, to act as a closure and constrictingmeans for the outlet opening. said oil supply connection opening intosaid chamber out of the path of movement of said deflector, and beingcontinually in communication with the chamber irrespective of themovement of the deflector. I

G. A carbureter comprising a chambe having air inlet and mixture outletopenings, and having an inwardly extending lip around the outlet openingan oil supply connection to said chamber, means for applying suction tothe outlet opening, a valve device controlling the inlet opening and adeflector connected to the valve device and of approximately the samediameter as the outlet opening, to act as a closure and constrictingmeans for the outlet opening, and means for retarding the movement ofsaid valve device and deflector, said oil supply connection opening intosaid chamber out of the path of movement of said deflector, and beingcontinually in communication with the chamber irrespective of themovement of the deflector.

T. A carburetor comprising a tubular chamber having a mixture outlet atits upper end and provided with air inlets on its side, a sleeve movablewithin said tubular chamber and provided with ports cooperating with theair in lets, means for adjusting the longitudinal and circumferentialposition of said sleeve, 21 valve member slidable within said sleeve andcontrolling the ports thereof, and a deflector connected to said valveand extending in proximity to the outlet of the chamber for the purposeset forth.

A carburetor comprising a chamber provided with outlet and air inletopenings, an oil supply connection opening into said chamber below theoutlet opening, valve means controlling and constricting the air inletopenings, :1 deflector controlling the outlet opening and concentratingthe flow of air therethrough to cause spraying of the oil and a throttlevalve and mixing chamber connected to the aforesaid chamber andcommunicating directly with the outlet opening thereof, said throttlevalve and mixing chamber having an outlet in its upper portion and avalve member controlling said outlet.

9. In combination with a carbureter, a throttle valve and mixing chamberhaving similar outlets in its upper and side walls, a valve membermounted in said chamber and coiiperating with both of said outlets, anda plug interchangeably fitting said outlets.

In testimony whereof, I have hereunto set my hand at Los AngelesCalifornia this 24th day of January 1905.

ALFRED C. STEWART.

In presence of- A. I. Kxicnr, JULIA Townsurm.

